Combined mr-optical coil for prostate-, cevix- and rectum cancer imaging diagnostics

ABSTRACT

We present, in exemplary embodiments of the present invention, a system combining anatomical imaging technologies (e.g., MR) with optical technologies. The system can be used for a variety of applications, including, but not limited to, (1) cancer diagnosis and staging; (2) image guidance; and (3) radiation therapy planning. Image guidance may include guiding a biopsy. For example, a prostatectomy potentially has severe side effects, such as impotence and incontinence. Thus, a histologically-confirmed diagnosis, such as one provided from a biopsy, may prevent unnecessary prostatectomy. Image guidance may also include guiding minimal invasive therapy, such as brachytherapy focused ultrasound. The present invention may be used to plan radiation therapy, for example, by detecting, and thus sparing, healthy tissue from radiation exposure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application No.60/541,102, which was filed on Feb. 2, 2004, and which is fullyincorporated herein by reference.

This application is related to U.S. patent application Ser. No. ______(Provisional Ser. No. 60/541,022), entitled “Combined MR-Ultrasound (US)Coil for Prostate-, Cevix-, and Rectum Cancer Imaging Diagnostics” filedon Jan. 27, 2005 and U.S. patent application Ser. No. ______(Provisional Ser. No. 60/541,020), entitled “Combined Intra-RectalOptical-MR and Intra-Rectal Optical-US Device for Prostate-, Cevix-,Rectum Imaging Diagnostics” filed on Jan. 27, 2005 both of which arefully incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to the field of medical imaging,and, more particularly, to combined magnetic resonance-optical coil forprostate, cervix and rectum imaging.

2. Description of the Related Art

Various diagnostic imaging methods are currently used for the diagnosisof prostate, cervix and rectum cancers. Modern diagnostic imagingtechniques include magnetic resonance (“MR”), computer tomography(“CT”), ultrasound (“US”) and nuclear medicine (e.g., Positron EmissionTomography (“PET”), Single Photon Emission Computed Tomography(“SPECT”)). A more accurate diagnosis can be provided by combining thedifferent imaging techniques. In particular, anatomical information(e.g., bones and organs) from an anatomical imaging technique may beenriched with optical information from an optical imaging technique.

The different imaging techniques are typically combined duringpost-processing. Post-processing is generally time-consuming. Further,accurate combinations of anatomical and optical modalities are generallyonly possible with rigid structures, such as the brain. However, eventhe brain has minor movement, which can potentially render thecombinations inaccurate.

SUMMARY OF THE INVENTION

In one aspect of the present invention, an apparatus for providinganatomical and optical diagnostic imaging is provided. The apparatusincludes an anatomical imaging unit for inserting into a body cavity,wherein the anatomical imaging unit acquires anatomical images of thebody cavity; and an optical imaging unit operatively connected to theanatomical imaging unit, wherein the optical imaging unit acquiresoptical information of the body cavity.

In another aspect of the present invention, an apparatus for providinganatomical and optical diagnostic imaging is provided. The apparatusincludes a sheath encompassing a magnetic resonance coil. Opticalcompounds are integrated into the coil to facilitate the detection offluorescence, preferably near infra red fluorescence.

In yet another aspect of the present invention, a method is provided.The method includes inserting a combined anatomical-optical device intoa body cavity; and receiving a combined image from the combinedanatomical-optical device, wherein the combined image displaysanatomical imaging-based information and optical imaging-basedinformation

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be understood by reference to the followingdescription taken in conjunction with the accompanying drawings, inwhich like reference numerals identify like elements, and in which:

FIG. 1 depicts a combined MR-Optical device, in accordance with oneexemplary embodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Illustrative embodiments of the invention are described below. In theinterest of clarity, not all features of an actual implementation aredescribed in this specification. It will of course be appreciated thatin the development of any such actual embodiment, numerousimplementation-specific decisions must be made to achieve thedevelopers' specific goals, such as compliance with system-related andbusiness-related constraints, which will vary from one implementation toanother. Moreover, it will be appreciated that such a development effortmight be complex and time-consuming, but would nevertheless be a routineundertaking for those of ordinary skill in the art having the benefit ofthis disclosure.

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof have been shown by wayof example in the drawings and are herein described in detail. It shouldbe understood, however, that the description herein of specificembodiments is not intended to limit the invention to the particularforms disclosed, but on the contrary, the intention is to cover allmodifications, equivalents, and alternatives falling within the spiritand scope of the invention as defined by the appended claims. It is tobe understood that the systems and methods described herein may beimplemented in various forms of hardware, software, firmware, specialpurpose processors, or a combination thereof.

We present, in exemplary embodiments of the present invention, a systemcombining anatomical imaging technologies (e.g., MR) with opticalimaging technologies. The system can be used for a variety ofapplications, including, but not limited to, (1) cancer diagnosis andstaging; (2) image guidance; and (3) radiation therapy planning. Imageguidance may include guiding a biopsy. For example, a prostatectomypotentially has severe side effects, such as impotence and incontinence.Thus, a histologically-confirmed diagnosis, such as one provided from abiopsy, may prevent unnecessary prostatectomy. Image guidance may alsoinclude guiding minimal invasive therapy. The present invention may beused to plan radiation therapy, for example, by detecting, and thussparing, healthy tissue from radiation exposure.

We propose a combined magnetic resonance-optical (“MR-Optical”) imagingdevice which is inserted into an accessible body cavity, such as therectum or the vagina. An optical probe is integrated into a magneticresonance (“MR”) coil for enriching magnetic resonance-based images withoptical-based information.

The combined MR-Optical device may be inserted into a body cavity and acombined image displaying anatomical imaging-based information andoptical imaging-based information is received. The combined image may beused for any of a variety of practical applications, as contemplated bythose skilled in the art, such as diagnostics (e.g., cancerdiagnostics), application guiding and therapy planning.

Referring now to FIG. 1, an exploded view of a MR-Optical device 100with combined MR imaging and optical imaging functionality is shown, inaccordance with one exemplary embodiment of the present invention. TheOptical-MR device 100 includes an optical probe 105, an MR coil 110, asheath 115, and a handheld component 120. The optical probe 105 may be atrans-rectal optical transducer. The optical probe 105 may be pushedand/or pulled relative to the MR coil. The optical probe 105 may alsorotate independently of the MR coil 110. The handheld component 120allows a user to easily grip and handle the MR-Optical device 100.Optical compounds could be integrated into the coil. The opticsfacilitate the detection of fluorescence, preferably near infra redfluorescence. The measured fluorescence could be due toauto-fluorescence or an applied fluorescence probe (contract agent),which could be specific for the cancer type under investigation. Thedevice could be used to detect activatable probes (smart probes).

The sheath 115 comprises a rigid housing, preferably transluminescentand filled with a coupling liquid (not shown). The coupling liquidpreferably has the same optical index as the surrounding material toprevent bending of illumination light beams (described in greater detailbelow).

The MR-Optical device 100 includes an optical wire 125 operativelyconnected to an optical device 130. The MR-Optical device 100 furtherincludes an MR wire 135 operatively connected to an amplifier 140. Theoptical wire could be lead through the center of MR coil 110 to theterminal detector/illuminator lead (optical probe 105). The optical wire125 and the MR wire 135 may be parallel. The optical wire connects thehead with an external light source and detector 130. It should beappreciated that, although not shown for the sake of simplicity, theamplifier 140 may be a component of a magnetic resonance tomography(“MRT”) unit, as known to those skilled in the art. It should further beappreciated that although only one wire is shown, the Optical wire andthe MR wire may include more than one wire, as contemplated by thoseskilled in the art. The MR coil 110 is preferably constructed to betranslucent (e.g., the spacing between the wires may be made out of atranslucent plastic, the coil wires are constructed to be stable withouta matrix/support).

In an alternate embodiment, the sheath 115 may be replaced with a lighttransparent balloon (not shown). The balloon may comprise a foldableinvestigation head with a liquid pump that fuels rotation. The sheath115 and the balloon encompass the assembly of MR coil 110. The sheath115 and the balloon may fix the MR-Optical device 100 to the bodycavity. For example, when the MR-Optical device 100 is inserted in thebody cavity, the balloon may be inflated. The balloon is preferablyinflated with a coupling liquid, but, in an alternate embodiment, may beinflated with air. If a transparent balloon is used, the MR coil 110(e.g., RF coil, bird cage) may be a flexible coil, such as theMRInnervu® commercially distributed by MEDRAD® Incorporated.

Furthermore, the sheath 115 and the balloon may be any of a variety ofshapes (e.g. toric) as contemplated by those skilled in the art. Thesheath 115 and the balloon are preferably shaped such that theMR-Optical device 110 can easily penetrate the particular body cavitybeing examined. Although only one balloon is described here, it shouldbe appreciated that more than one (e.g., two) balloons may be used, ascontemplated by those skilled in the art.

The optics can cover a 360 degree view or any limited angle. In thelater case, the lead might be revolved from outside (independently ofthe MR coil). In both designs the optical lead can be push/pulledrelatively to the MR coil. The balloon may not cover the optical lead.Illumination and light detection is not restricted by the balloon or bythe coil. The balloon might be toric or two balloons might be used.

Illumination and fluorescent light could be guided by two separatewires. Alternative modulation techniques could be used to distinguishbetween illumination and fluorescent light. A particular design mightoperate in a CW (continues Wave) mode. Other designs might apply TD(time domain) measurements, OCT (optical tomography) or 2-Photonemeasurements. Tomographic methods might be applied to increasesignal-to-noise or increase tissue penetration.

For the design of the optics, three general embodiments of the opticsare possible. 1. Light wire (single fiber or fiber bundle) feeds acircular diffuser or discrete microscopic lenses assembled in a circle.The optical head is moved along the MR axis to get a good coverage ofthe cavity. 2. There is a rotating mirror at the end of the light wire,which projects the illumination light circularly on the cavity wall(e.g. rectum epithelia) and captures fluorescent light. The mirror isconnected to a cardan shaft and motor that is located outside of themagnetic field. The optical head is moved along the MR axis to get agood coverage of the cavity. 3. There is a DMA (Digital Mirror Array),which projects the light in two or three dimension.

The following light sources are possible; broadband light source (e.e.xenonlamp or mercury lamp), LED or LED array, or a laser. The detectorcould be a CCD camera or a CMOS. All materials for the optics arenonconductive. If this is not feasible, conductive material has to be assmall and thin as possible to keep HP coupling minimal.

The intra-rectal measurements obtained from the MR-Optical device 100are preferably combined with an external phased array coils (not shown)for increasing signal-to-noise and increasing the area of the bodycavity being examined. The external phased array coils are a typicalcomponent of a standard MRT unit. In one embodiment, the external phasedarray coils may be body arrays, providing ventral and dorsal receiverchannels. The body arrays expand the viewable area in the body cavity,which provides information of lymph nodes for, for example, staging.

The MR-Optical device 100 may also be combined with monocrystalline ironoxide nanoparticles (“MION”), which is an MR contrast agent. The MIONmay be dually labeled with a fluorescence dye, which is an opticalcontrast agent. Further, the MR data set (i.e., the image obtained fromthe MRT unit using the present invention) may be used for segmentationand subsequence modeling of NIRF absorption and auto-florescence forincreasing the NIRF image quality.

The particular embodiments disclosed above are illustrative only, as theinvention may be modified and practiced in different but equivalentmanners apparent to those skilled in the art having the benefit of theteachings herein. Furthermore, no limitations are intended to thedetails of construction or design herein shown, other than as describedin the claims below. It is therefore evident that the particularembodiments disclosed above may be altered or modified and all suchvariations are considered within the scope and spirit of the invention.Accordingly, the protection sought herein is as set forth in the claimsbelow.

1-20. (canceled)
 21. An apparatus for providing anatomical and molecular diagnostic imaging, comprising: a magnetic resonance (MR) coil for inserting into a body cavity; and an optical component operatively integrated into the MR coil, the optical component for detecting fluorescence in the body cavity.
 22. The apparatus of claim 21, wherein the optical component detects near infra-red fluorescence.
 23. The apparatus of claim 21, wherein the optical component moves relative to the MR coil.
 24. The apparatus of claim 21, wherein the optical component rotates independent of the MR coil.
 25. The apparatus of claim 21, wherein movement of the optical component is reproducible.
 26. The apparatus of claim 21, further comprising a handheld component operatively connected to the MR coil.
 27. The apparatus of claim 21, wherein the MR coil comprises a flexible coil.
 28. The apparatus of claim 21, further comprising a sheath encompassing the MR coil.
 29. The apparatus of claim 28, wherein the sheath comprises at least one light-transparent balloon for inflation after insertion into the body cavity to fix the MR coil in the body cavity.
 30. The apparatus of claim 29, wherein the light-transparent balloon comprises toric.
 31. The apparatus of claim 21, wherein the MR coil is operatively connected to a magnetic resonance amplifier.
 32. The apparatus of claim 21, further comprising a first wire for receiving data from the MR coil and a second wire for receiving data from the optical component.
 33. The apparatus of claim 21, further comprising a modulation component for distinguishing between data from the MR coil and data from the optical component.
 34. The apparatus of claim 21, wherein the optical component comprises a light wire for projecting illumination light and an optical head for detecting fluorescence.
 35. The apparatus of claim 34, wherein the light wire comprises at least one fiber, and wherein the at least one fiber feeds one of a circular diffuser and discrete microscopic lenses assembled in a circle.
 36. The apparatus of claim 34, further comprising a rotating mirror operatively connected to one end of the light wire, the rotating mirror for circularly projecting the illumination light in the body cavity.
 37. The apparatus of claim 21, wherein the optical component comprises a digital mirror array.
 38. The apparatus of claim 21, further comprising a light source.
 39. The apparatus of claim 38, wherein the light source comprises one of a broadband light source, a light-emitting diode (LED), and a laser.
 40. The apparatus of claim 21, further comprising a phased array of MR coils for increasing signal-to-noise ratio and increasing the region of investigation.
 41. A method, comprising: inserting a magnetic resonance (MR) coil with an integrated optical component into a body cavity; and receiving combined data from the MR coil, wherein the combined data comprises MR-based data and fluorescence detection data.
 42. The method of claim 41, further comprising: applying a contrast agent in the body cavity.
 43. The method of claim 41, wherein the step of inserting a magnetic resonance (MR) coil with an integrated optical component into a body cavity comprises inserting a magnetic resonance (MR) coil with an integrated optical component into a body cavity into one of a prostate, a cevix, and rectum.
 44. The method of claim 41, further comprising analyzing the combined data for one of diagnostics, application guiding and therapy planning.
 45. An apparatus for providing anatomical and molecular diagnostic imaging, comprising: a magnetic resonance (MR) coil for inserting into a body cavity, wherein the MR coil comprises a light-transparent balloon for fixing the MR coil in the body cavity; an illumination source operatively integrated into the MR coil, the illumination source for providing illumination light in the body cavity; and an optical head operatively integrated into the MR coil, the optical head for detecting fluorescence in the body cavity. 